How And When to Use Paste Wax
by Sal Marino
Contrary to popular belief, paste wax is not a
good choice for a protective finish. Even though you may read
articles or hear other woodworkers advocating the use of paste wax as a
protective finish for raw wood, the simple fact is that when it comes to
protection, paste wax is very inferior compared to oil finishes or
topcoat finishes like lacquer, varnish, polyurethane etc. It is true
that wax was used for centuries as a wood finish, but that was before
the advent and discovery of oil finishes and film finishes. Wax provides
no significant protective barrier for wood against heat, water, water
vapor or chemical spills such as from an alcoholic beverage. Wax is very
soft and never dries to a hard finish. Its melting point is approx. 140
degrees F, which is way too low to protect against any kind of hot
object. Even a cup of hot coffee placed on a tabletop that has been
finished with wax only will melt the wax right through to the wood.
Because wax is so soft, most of the excess applied needs to be wiped off
in order to achieve a clear and polished surface, therefore the film
surface of a wax finish is way too thin to protect wood against water or
moisture (water vapor). Even milder solvents like mineral spirits (paint
thinner) and turpentine will dissolve wax almost immediately, therefore
it has no resistance to chemical spills.
Wax can be an effective barrier against water vapor when applied in a
thick coating to the end grain of boards or freshly cut wood. Because it
is applied in such a thick coating, it prevents the moisture from
escaping too quickly, thus the freshly cut boards or wood will not
check.
About the only protection
wax affords is against
abrasion, and even that is
not significant. It's not
the actual film of wax that
protects wood against
abrasion, because the film
is too thin for that. Wax
makes the surface slippery,
thus objects slide across a
waxed surface, rather than
digging in and scraping. You
must remember that wood
needs more than just
abrasion protection. A piece
of furniture that has only
wax to protect it will soon
become dirty and will have
no water, water vapor or
chemical protection. A wax
finish will soon become
filled with dust and dirt
that will stick to it and
create a dull, dark ugly
mess. The only way to fix
this is to remove all the
wax, clean the wood and sand
the surface to prepare it
for another finish.
However, when applied properly, and for the right reason, paste wax can
be very effective and add beauty and color back to an old piece of
furniture. A wax finish can be very effective on a carved or turned
object that receives very little handling, especially when you want a
low sheen and don't want to change the natural color of the wood too
much.
Paste wax is best used as a polish over an existing finish such as
lacquer, shellac, polyurethane or even oil finishes. As
mentioned, it will give you a little extra protection against scratches,
but most modern finishes like polyurethane and newer finishes are very hard to begin with and usually the finish alone is
abrasion resistant enough. Thus, using paste wax to maintain and
regularly care for your furniture is by far the best reason to use paste
wax today. A paste wax will add shine to a surface by filling in small
scratches or voids. The finish will appear shiner and deeper
because the light that was getting trapped in those scratches and voids
before the wax was applied, is now reflecting off the surface. On darker
pieces of furniture it's best to use a dark colored paste wax. This will
not only polish the piece but also hide some minor scuffs and scratches.
Many people believe that pure beeswax is the best choice for use among
paste waxes. This is not true. True, in the past beeswax was often used,
but that was because it was the only wax available. Today, paste wax
manufactures blend natural waxes like beeswax and harder carbuna wax
with synthetic waxes. The waxes are selected for cost, color, slip
resistance and hardness. This blend of waxes makes a paste wax that is
harder and in many other ways superior to pure beeswax, which is also
very expensive in pure form. Waxes like carnuba are much harder than
bees wax, but are too hard to be used alone without blending with other
softer waxes.
All waxes are originally solid. They are made into a paste by being
dissolved into a solvent. Years ago, turpentine was used as the solvent,
but today petroleum distillate solvents such as mineral spirits, and
toluene are generally used to dissolve the waxes.
Most commercially made paste waxes are very similar in their quality and
the sheen they produce. In fact, you can take the ten top brands of wax,
apply them side by side to a finished surface and not see any
significant difference in gloss or sheen. About the most significant
difference in these waxes is in the amount of time you need to wait
before wiping off the excess and buffing out the wax. Certain waxes like Briwax use a quicker evaporating solvent like toluene. Because these
solvents evaporate quicker, the wax turns back to solid quicker,
(becoming hazy) and once the wax hazes over, it's time to wipe off the
excess and buff it out. Other waxes with slower evaporating solvents
like mineral spirits will take longer to turn back to solid and haze
over.
Applying Paste Wax
Many manufactures of furniture polishes and furniture care products
always talk about wax build up. Some have even produced special products
that eliminate wax build up. This is ridiculous because there is no such
thing as wax build up. When you apply wax, you must remove approx. 99
percent of it when you buff it out. If not, you will never attain a
shine. You must only leave a very thin layer on the surface. Therefore,
there can be no such thing as wax build up.
Make sure that the surface of your finish is clean and free of any dirt.
If not, clean it with a mild soap like Murphy's Oil Soap and water. Take
a piece of lint free soft cotton cloth and put a lump of paste wax in
the center of the cloth. This will limit the amount of wax you apply to
the surface and you need not have to continue to dip into the can. Twist
the cloth into a ball and kneed it in your hand to soften the wax a
little. Apply the cloth over the surface of the finish letting the wax
seep through the cloth onto the surface. You can apply the wax in any
direction, using any motion, straight, circular, with grain, against
grain etc. When the wax is first applied, it glossy because of the
amount of solvent in it. As the solvent evaporates, it will start to
turn back to solid and the surface will become hazy. If you wait too
long the wax will be difficult to remove. If this happens, don't worry,
just take some fresh wax apply it over the hardened wax and wipe it off
right away. The solvent in the fresh wax will re soften the hard wax
again and you can remove it. If you don't wait long enough, you will
still be removing all the wax and you will have no sheen at all. Work on
small areas at a time until you get used to how long you need to wait
until the wax has hazed and the excess needs to be removed. Wipe off the
excess with a clean piece of lint free soft cotton cloth. Buff the
surface with the cloth until you achieve a even sheen.
WARNING:
DO NOT USE SOLVENT BASED WAXES ON ANY FINISH
THAT HAS NOT CURED FULLY. THE SOLVENT IN THE WAX MAY HARM THE FINISH. |